Cellulose-nitrate composition and process of making the same



UNITED STATES PATENT omen.

STEWART J. CARROLL, OF ROCHESTER, NEW YORK, ASS'IGNOR TO EASTMAN KODAK COMPANY, OF ROCHESTER, NEW YORK, A CORPORATION OF NEW YORK.

CELLULOSE-NITRATE COMPOSITION AND PROCESS OF MAKING THE SAME.

No Drawing.

the same, in which a cellulose nitrate com pound is combined or mixed with other substances, so that the resulting product can be advantageously used in the plastic and analogous arts, such, for instance, as sheet or film manufacture and varnish manufacture.

One object of my inventionis to provide a composition of matter in which the crystallization or partial separation of certain of the essential ingredients will be prevented. Another object of my invention is to provide a method of combining the ingredients homogeneously, so that in the resulting composition they will stay permanently homogeneous. A further object of my invention is to provide a composition in which the inflammability is reduced to an important extent below that of ordinary compositions containing cellulose nitrate.

Yet another object is to produce a composition which may be made into permanently transparent, strong and flexible sheets of film of desired thinness that are substantially waterproof, are unaffected by ordinary photographic fluids' and possess the desired properties of a su port for sensitive photographic coatings. till another object is to produce a composition which is capable of easy manipulation in the film making' or varnish making arts; which will not injure or be injured bythe substances'with which it is associated during manufacture,

storage, or use. Further objects will hereinafter appear.

. It is well known that pyroxylin compounds tend to burn with rapidity, so that when present in the form of sheets or films, such as are used in motion. picture projectors, for example, precautions against fire are advisedly taken. I have found that a composition with which the fire risk is lessi ened and one having the desirable quantities Specification of Letters Patent.

Patented Oct. 5, 1920.

Application filed January 2, 1920. Serial No. 349,052.

hereinabove enumerated can be obtained by m xlng or compounding cellulose nitrate with crystalline or waxy higher chlorin derivities of the cyclic hydrocarbons C H and their homologues, such as tri or tetrachlor naphthalenes or anthracenes. Furthermore this compounding is preferably performed by mixing the ingredients with a solvent common to both, like methyl alcohol of the grade used in the pyroxylin arts. If, however, the waxy body alone is thus compounded with the cellulose nitrate in serviceable amounts, it tends to separate out or crystallize on the surface of the varnish or film when the volatile common solvent evaporates, thus rendering it imperfeet, for some purposes, particularly impairing the transparency needed in the photographic art. I have discovered that this undesirable separation may be prevented by incorporating phenyl esters, like triphenyl phosphate and its derivatives and homolo es, into the compound along with the c' or body. Such phenyl esters are peculiarly desirable as fixers of the chlor body, because they not only retain such body in its amorphous or colloidized state, but also tend to decrease the combustibility of the resulting composition, being themselves substantially noncombustible. When flexi bility should be emphasized, as in photographic film, I also may add substances like the aliphatic alcohols of more than two carbon atoms,-for instance, fusel oil or the various butyl alcohols which have only slight volatility.

The waxy chlor bodieswhich I employ are so substantially non-volatile that any loss under the conditions prevailing during the use and desired life of the film will not make the latter unserviceable. As applied to my compounds, the term non-inflammable means, of course, only practical noninflammability, the chlor bodies themselves not acting normally to propagate combustion but rather being strongly flame resisting. They impart this quality to a very useful degree to the composition in which I in-\- range of 310 C. to 340 C. It is especially non-inflammable.

In carrying out one illustration of my invention I incorporate with 100 parts of cellulose nitrate 475 parts of methyl alcohol, 40 parts of fusel oil, 30 parts of triphenyl phosphate and 5 parts of the waxy chlor body mentioned hereinabove in the preceding paragraph. As before explained, the fusel oil is optional but is preferable where enhanced flexibility is desired. In

combining the ingredients, the cellulose nitrate and fusel oil are thoroughly mixed with the methyl alcohol while the triphenyl phosphate and waxy chlor body are separately combined by means of a small portion of acetone, say 10 parts. This triphenyl phosphate-chlor body mixture is then thoroughly stirred into the cellulose nitrate-fusel oil mixture to form a homogeneous solution or flowable mass, which may be filtered if desired. The pre-mixing of the triphenyl phosphate with the chlor body facilitates the introduction of the latter into the mixture and its continued presence keeps the chlor body from changing to the crystalline form or separating out.

This solution is sufficiently thick and viscous to be properly flowed during sheet or film manufacture, the methyl alcohol volatilizing but not' too rapidly to impair the product. The resulting film containing the non-volatilized ingredients is so flexible, smooth, transparent and uniform that it may be used for any usual or preferred purpose. Due to its reduced inflammability, its fire risk is very much diminished. It is practically waterproof and is unaffected by ordinary photographic chemicals. The chlor body, having the halogen in the ring or closed chain, is very stable. so that chlorin is not liberated in sufiicient amounts to injure metal or other parts with which it comes in contact during manufacture and,

moreover, does not chemically re-act with or injure other bodies that it is associated with in the solution or film, even when the latter is coated with sensitive emulsion.

While I have herein disclosed certain compositions and processes by way of example, my invention is not limited to the proportions given therein, as my experiments indicate that the proportions may be widely varied from those given in order to adapt the composition to particular uses. Furthermore equivalent substances may be substituted, such, for instance, as the solvent acetone in place of methyl alcohol.

aving thus described my invention, what claim as new and desire to secure by Letters Patent is:

1. A composition of matter comprising cellulose nitrate, a waxy higher chlorin derivative of the cyclic hydrocarbons O l-1 and their homologues and a non-inflammable compound for tion of said chlorin derivative.

2. A composition of matter comprising cellulose nitrate, a waxy higher chlorin derivative of the cyclic hydrocarbons C W and their homologues, a non-inflammable compound for reventing separation of said chlorin derivatlve and a common solvent.

A composition of matter comprising cellulose nitrate, a waxy higher chlorin derivative of the c clic hydrocarbons C H and their homologues, a non-inflammable compound for preventing separation of said chlorin derivative and an organic body of slight volatility which enhances the flexibility of the composition.

4. A composition of matter comprising cellulose nitrate, tetrachlor naphthalene and a phenyl ester for keeping said tetrachlor naphthalenein the colloidized state.

A composition of matter comprising cellulose nitrate, tetrachlornaphthalene and triphenyl phosphate.

6. A composition of matter comprising cellulose nitrate, tetrachlornaphthalene, a phenyl ester for keeping said tetrachlornaphthalene in the colloidized state and an organic body of slight volatility which enhances the flexibility of the composition.

7. A composition of matter comprising cellulose nitrate, tetrachlornaphthalene, triphenyl phosphate and fusel oil.

8. A composition of matter comprising cellulose nitrate, tetrachlornaphthalene, a phenyl ester for keeping said tetrachlornaphthalene in the colloidized state and a common solvent."

9. A composition of matter comprising cellulose nitrate, tetrachlornaphthalene, triphenyl phosphate, fusel oil and methyl alcohol.

10. A composition of matter comprising preventing separa- 12. As an article of manufacture, a sheet of deposited or flowed cellulose nitrate containing tetrachlornaphthalene and ester for keeping said tetrachlornaphthalene in the colloidized state.

13. As an article of manufacture, a sheetof deposited or flowed cellulose nitrate containin tetrachlornaphthalene and triphenyl phosp ate.

14. As an article of manufacture, a sheet a phenyl of deposited or flowed cellulose nitrate containing tetrachlornaphthalene, triphenyl phosphate and fusel oil.

15. The process of making a composition of matter which comprises the step of combining tetrachlornaphthalene and tri'phenyl phosphate by the aid of a common solvent and then combining the resulting mixture with a solution containing cellulose nitrate.

16. The process of making a composition of 10 matter which comprises first colloidizing tetrachlornaphthalene and triphenyl phosphate together and then combining the resulting mixture with a solution containing cellulose nitrate and fusel oil. 15

Signed at Rochester, New York, this 23d clay of December, 1919.

STEWART J. CARROLL. 

